Known electronic devices, generally of parallelepiped shape, include a supporting substrate, including an electrical connection network, an integrated circuit chip mounted on one of the faces of the supporting substrate and an encapsulation block in which the chip is embedded. The chip is connected to the network of the supporting substrate by electrical connection elements such as balls, disposed between the supporting substrate and the chip, or by electrical connection wires embedded in the encapsulation block.
Such electronic devices are mounted on printed circuit boards, generally via electrical connection elements such as balls, connecting the electrical connection network of the supporting substrates and the electrical connection network of the printed circuit boards.
When the chips generate radio signals that have to be transmitted or process received radio signals, the sending or receiving antennas are produced on the printed circuit boards. The electrical signals follow very long resistive paths that consist of lines of the electrical connection network of the printed circuit boards, the electrical connection elements between the printed circuit boards and the supporting substrates, lines of the electrical connection network of the supporting substrates and the electrical connection elements between the supporting substrates. Such paths also depend on the quality of the interconnections resulting from the process of manufacture.
The above arrangements constitute a handicap, notably when the necessary size of the antennas for the transmission of radio signals at frequencies of the order of 1 GHz and above, and even very much higher than 1 GHz, is small.